Page 44 - 《广西植物》2026年第4期
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analyses of their sequence characteristicsꎬ encoded protein propertiesꎬ promoter cis ̄acting elementsꎬ gene structuresꎬ
and phylogenetic relationships. Quantitative real ̄time PCR (qRT ̄PCR) was employed to detect the expression patterns
of these genes in different tissues and during fruit ripening. The results were as follows: (1)A total of seven kiwifruit
AcPAL genes were identified and designated as AcPAL1-AcPAL7ꎬ respectively. The proteins encoded by the AcPAL family
genes consisted of 706 - 722 amino acidsꎬ and all of them were stable acidic proteins. These proteins possess the
conserved domain ( PLN02457) and active site motif ( GTITASGDLVPLSYIA). (2) Chromosomal localization and
collinearity analyses revealed that one tandem duplication event and ten segmental duplication events were the major
driving forces for the expansion of the AcPAL family members. (3)Phylogenetic tree analysis indicated that all AcPAL
family members clustered within the dicotyledon clade and showed a close genetic relationship with CsPAL proteins from
Camellia sinensis. (4) The promoters of AcPAL family genes contained various cis ̄acting elements involved in light
responseꎬ stress responseꎬ hormone responseꎬ as well as growth and development regulation. (5) qRT ̄PCR results
showed that different AcPAL members exhibited differential expression patterns in rootsꎬ stemsꎬ leavesꎬ flowers and fruits
of kiwifruit. Notablyꎬ four members (AcPAL2ꎬ AcPAL3ꎬ AcPAL4 and AcPAL5) were significantly up ̄regulated during
postharvest fruit ripening. This expression pattern was consistent with the marked increase in PAL enzyme activityꎬ and
their expression was induced by abscisic acid (ABA). These findings provide candidate genes and a theoretical basis for
further investigation into the functions of AcPAL genes in the formation of postharvest fruit quality in kiwifruit.
Key words: kiwifruit (Actinidia chinensis)ꎬ phenylalanine ammonia ̄lyase (PAL)ꎬ family gene characteristicsꎬ fruit
ripeningꎬ expression patterns
猕猴桃是 20 世纪 80 年代发展起来的新兴水 则分别含有 9 个 OsPALs ( Gho et al.ꎬ 2020) 和 12
果作物ꎬ其果实富含抗坏血酸、酚类等多种生物活 个 GhPALs ( 李 雨 哲 等ꎬ2021)ꎮ 诸 多 研 究 表 明ꎬ
性物质ꎬ深受消费者喜爱( Yu et al.ꎬ 2020ꎻ Zhu et PAL 基因参与植物的生长发育及果实成熟等生物
al.ꎬ 2022)ꎮ 猕猴桃果实在发育成熟过程涉及大 学过程ꎮ 美洲南瓜 PAL 基因在自交授粉 20 d 后的
量酚类等次生代谢物质的生成与转化( 黄春辉等ꎬ 有壳品种中表达上调ꎬ而在露仁品种中表达下调ꎬ
2019)ꎮ 有研究表明ꎬ次生代谢产物的积累与代谢 其在不同品种中的差异表达影响种皮发育ꎬ进而
对猕猴桃果实品质形成具有重要影响( Yu et al.ꎬ 形成有壳或露仁性状(刘佳等ꎬ2014)ꎻ蜜柚果实发
2020ꎻ Wang et al.ꎬ 2022)ꎮ 苯丙烷代谢通路是植 育过程中 CmPAL3 的表达量与木质素含量显著相
物产生次生代谢产物的主要途径之一ꎮ 苯丙氨酸 关(黄汉唐等ꎬ2020)ꎻ香蕉 MaPAL4 在果实后熟过
解氨酶(phenylalanine ammonia ̄lyaseꎬ PAL) 是该通 程中特异性上调表达(杨会晓等ꎬ2019)ꎻ软枣猕猴
路的起始酶与限速酶ꎬ能够催化 L ̄苯丙氨酸生成 桃 PAL 基因( TRINITY_DN6191_c0 ̄g1) 在果实发
反式肉桂酸ꎬ进而形成黄酮类、木质素、酚苷等多 育过程中上调表达ꎬ与花色苷积累趋势一致( Niu
种苯丙烷类化合物ꎬ在植物的生长发育及果实成 et al.ꎬ 2022)ꎻ毛花猕猴桃果实 PAL 基因( DTZ79_
熟中 发 挥 重 要 作 用 ( Shahidi et al.ꎬ 2024ꎻ An et 15g06470)的表达量则与多酚类物质(4 ̄咖啡酰奎
al.ꎬ 2025)ꎮ 宁酸 和 山 奈 酚 ̄3 ̄O ̄葡 萄 糖 苷) 的 积 累 高 度 相 关
苯丙氨酸解氨酶广泛存在于植物、藻类、真菌 (Jia et al.ꎬ 2022)ꎮ 作 者 课 题 组 前 期 在 脱 落 酸
及酵母中ꎮ 植物苯丙氨酸解氨酶由多基因家族编 (abscisic acidꎬ ABA)促进猕猴桃果实采后成熟的
码ꎬ目前已陆续从海南粗榧( He et al.ꎬ 2020)、香 转录组研究中发现ꎬ部分 PAL 基因呈现显著差异
蕉(杨会晓等ꎬ2019)、水稻(Yu et al.ꎬ 2018)、拟南 表达ꎬ推测 PAL 家族基因参与猕猴桃果实成熟过
芥(Cochrane et al.ꎬ 2004)、山核桃(刘晨等ꎬ2025) 程(Chen et al.ꎬ 2021)ꎮ 此外ꎬPAL 基因的转录水
和大豆( Rizwan et al.ꎬ 2025) 等多种裸子植物、单 平与其启动子区的顺式作用元件密切相关( Li et
子叶植物与双子叶植物中鉴定得到ꎮ 植物 PAL 家 al.ꎬ 2019)ꎮ 目前ꎬ虽已有猕猴桃部分 PAL 基因表
族的成 员 数 量 因 物 种 而 异ꎬ 如 拟 南 芥 含 有 4 个 达量的相关报道ꎬ但其家族成员的系统特征ꎬ以及
AtPALs (Cochrane et al.ꎬ 2004)ꎬ水稻和陆地棉中 该家族在不同组织、果实发育及成熟进程中的表

